logiguard fork: GPUI xdg-activation keyboard-focus serial fix

Single-commit orphan branch: full zed-industries/zed @ 8c74db0 source tree
with a 3-file patch applied (no upstream history).

Patch (crates/gpui_linux/src/linux/wayland/):
  - serial.rs: add SerialKind::KeyboardEnter
  - client.rs: store wl_keyboard.enter serial; add latest_serial_of()
  - window.rs: activate() uses keyboard-enter serial (Mutter focus gate)

Mutter honors window activation only when the token carries the keyboard-
focus serial from wl_keyboard.enter; GPUI used a stale mouse-press serial.
See docs/tray-window-focus-wayland.md in logiguard.

Co-Authored-By: Claude Fable 5 <noreply@anthropic.com>

docs/src/languages/scala.md

@@ -0,0 +1,34 @@
+---
+title: Scala
+description: "Configure Scala language support in Zed, including language servers, formatting, and debugging."
+---
+
+# Scala
+
+Scala language support in Zed is provided by the community-maintained [Scala extension](https://github.com/scalameta/metals-zed).
+Report issues to: [https://github.com/scalameta/metals-zed/issues](https://github.com/scalameta/metals-zed/issues)
+
+- Tree-sitter: [tree-sitter/tree-sitter-scala](https://github.com/tree-sitter/tree-sitter-scala)
+- Language Server: [scalameta/metals](https://github.com/scalameta/metals)
+
+## Setup
+
+- Install Scala with `cs setup` (Coursier): https://www.scala-lang.org/download/
+  - `brew install coursier/formulas/coursier && cs setup`
+- REPL (Almond) Setup Instructions https://almond.sh/docs/quick-start-install
+  - `brew install --cask temurin` (Eclipse foundation official OpenJDK binaries)
+  - `brew install coursier/formulas/coursier && cs setup`
+  - `coursier launch --use-bootstrap almond -- --install`
+
+## Configuration
+
+Behavior of the Metals language server can be controlled with:
+
+- `.scalafix.conf` file - See [Scalafix Configuration](https://scalacenter.github.io/scalafix/docs/users/configuration.html)
+- `.scalafmt.conf` file - See [Scalafmt Configuration](https://scalameta.org/scalafmt/docs/configuration.html)
+
+You can place these files in the root of your project or specifying their location in the Metals configuration. See [Metals User Configuration](https://scalameta.org/metals/docs/editors/user-configuration) for more.
+
+<!--
+TBD: Provide LSP configuration example for metals in Zed settings.json. metals.{javaHome,excludedPackages,customProjectRoot} etc.
+-->